The present invention relates to a manually operated thrust piston pump for the discharge, delivery or dispensing of media, with a piston unit displaceable in a cylinder counter to at least one bending spring more particularly made from plastic, the pump piston of said piston unit located in the pump axis defining a pump chamber with the cylinder.
A pump which can be mounted on a container of the present type is known (EP No. 00 73 918 A1), which comprises a pump pistoncarrying upper part, a cylinder-forming lower part and a discharge-nozzle carrying cover and which is assembled with the upper part. On the underside of the cover there are spiral springs constructed in one piece therewith and which are arranged in the form of circumferentially curved spring arms on a rim around the pump axis. By means of their free ends, the spring arms are supported on a partition of the lower part at right angles to the pump axis and which surrounds the pump chamber in annular manner. This leads to a very space-consuming housing of the spiral springs, unfavourable spring characteristics and a relatively difficult action of the springs.